Liquid fuel and atomizing ring for annular combustion chambers



March 6, 1951 w. L. CHRISTENSEN LIQUID FUEL AND ATOMIZING RING FOR ANNULAR COMBUSTION CHAMBERS Filed July 1 INVENTOR Mum0L.[//R/5TA 5[M ATTORNEY I 00 Dun n a km a v llllll 11 km o o o m m I! o o MM 0 a v j v M X 9 Mn mm Q UNITED STATES PATENT OFFICE LIQUID FUEL AND ATOMIZING RING FOR ANNULAR COMBUSTION CHAIHBERS Willard L. Christensen, Moylan, Pa., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application July 1, 1946, Serial No. 680,698

2 Claims. I This invention relates to combustion apparatus, more particularly to combustion chamber structure, and has for an object to provide novel structure of this character.

Fig. 1 is a side elevational view of a gas turbine power plant incorporating the present invention, a portion of the outer casing and part of the inner structure being broken away to better il- In combustion apparatus where liquid fuel is lustrate the novel features; supplied to a combustion chamber through atom- Fig. 2 is an enlarged sectional view of half of a izing nozzles, it frequently occurs under certain combustion chamber such as shown in the power conditions of operation that some of the fuel from plant of Fig. 1; the atomizing nozzles sprays onto the combus- Fig. 3 is an enlarged transverse sectional view, tion chamber walls and collects there in drops taken along the line III-III of Fig. 2, looking in or streams. Such fuel collection usually occurs the direction indicated by the arrows; and under conditions of high fuel rates and low air Fig. 4 is an enlarged fragmentary sectional flow, resulting in inefficient mixing of the fuel and view, taken along the line IV-IV of Fig. 3, lookair with consequent long flame and inefiicient ing in the direction indicated by the arrows. burning, or of low fuel rates, where the main The present invention, although not limited atomizing nozzles do not operate under sufficient thereto, is particularly adapted for use with a pressure to prevent fuel dribbling down onto the gas turbine power plant of the type employed on combustion chamber walls in rather large drops. aircraft to drive a propeller or an electric gen- To overcome this difficulty, the present invenerator or to supply motive fluid for jet propultion proposes the use of a fuel-collecting and sion of the aircraft. Such a plant preferably atomizing ring of trough-like cross section (115- comprises a streamlined tubular casing having posed against the inner surface of the combusmounted axially therein a compressor adjacent tion wall just downstream of the zone at which the forward or inlet end, a turbine adjacent the fuel tends to collect on said wall, with the trough rearward or discharge end, and combustion apopening upstream. paratus located adjacent the compressor and the The fuel deposited on the combustion chamturbine for heating the compressed air and which her walls collects in the trough of the ring and discharges the hot gases at suitable temperature is reatomized through atomizing openings proand pressure to the turbine. The spent gases vided in the bottom of the trough at spaced inon leaving the turbine are discharged through a tervals therealong. Additional air for this renozzle provided at the rear of the casing and may atomization enters the combustion chamber aid in propelling the aircraft. v through openings in the side walls of the latter Referring now to the drawing more in detail, in circumferential alignment with the atomizing the power plant shown in Fig. 1, and indicated openings of the trough-like ring, the air enterin its entirety by th reference character it, is ing through the side wall openings passing adapted to be mounted in or on the fuselage or through the aligned openings in the trough and wing of an aircraft with the left end or intake carrying with it the fuel collected in the trough, i I, as viewed in this figure, pointed in the direcin atomized streams. tion of flight.

Therefore, another object of the invention is The plant comprises an outer shell or casing to provide, in combustion apparatus, means for structure i2-i2a. providing an annular air duct trap ing liquid fuel collecting on the walls of the or passa e l3 extending fore and aft with recombustion chamber. spect to the aircraft. This casing has mounted A further object of the invention is to provide, h r in, along its longitudinal axis, a fairing in combustion apparatus, means for atomizing 11 I4 adapted o h e ring connectin liquid fuel collecting on the walls of the combus- 5 through a hollow guide Vane With a es tion chamber. (not shown), an axial-flow compressor l'l, com- Another object of the invention is to provide, ust n apparatus er ly di ated 8. a turin combustion apparatus, means for collecting e 9 Which drives the compressor. d o and atomizing liquid fuel deposited on the walls zle 2| defined by he ng 2 and y a a of the combustion chamber. piece 22, the latter being mounted concentrically These and other objects are effected by the in the casing and cooperating with the latter to invention as will be apparent from the following provide the propulsion nozzle. description and claims taken in connection with Air enters at the intake II and flows substanthe accompanying drawing, forming a part of this tially straight through the plant, passing through application, in which: the compressor I! where its pressure is raised,

' nected by means of a shaft 26 supported by suitable bearings 21 and enclosed by an inner wall structure, generally indicated 28, which protects the shaft and bearings from high temperatures and also defines a portion of the annular air flow passage I3 in which the combustion apparatus I8 is disposed.

The present invention is not limited to the specific details or arrangements of structure thus far' described, but is primarily concerned with the combustion apparatus, indicated generally at I8. A pair of frusto-conical inner and outer Wall members 3| and 32, respectively, separate the annular fiow passage I3, at the region of the combustion apparatus I8, into an annular burner space or combustion chamber 33 overlapped both inwardly and outwardly by annular air spaces 34 and 36, respectively. The inner wall 3| is disposed with its base or larger end upstream and the outer wall 32 has its larger end or base downstream, with the result that the burner space 33 defined thereby increases in cross-sectional area from its upstream end to its downstream end. Conversely, the inner and outer overlapping air spaces 34 and 35, the former defined by the walls 28 and 3| and the latter by the walls I20, and 32, decrease in crosssectional area from their upstream ends to their downstream ends.

Preferably, the upstream end of the burner space 33 is closed by an annular wall 36, in which is mounted an annular series of fuel nozzles 31 adapted to direct the fuel discharged therefrom downstream in directions generally parallel to the longitudinal axis of the power plant.

As previously pointed out, there are certain conditions of operation under which drops of liquid fuel form on the walls 3| and 32 in the region thereof just downstream of the nozzles 31. These drops tend to flow to the lowest point in the burner space and may cause hot spots when burning, or they may leak out of the combustion chamber and create a fire hazard.

In accordance with the present invention, liquid fuel-collecting and atomizing rings 4| and 42 are secured to the side walls 3| and 32, respectively, of the burner space 33 just downstream of the burner space wall area on which the fuel drops are deposited. Each ring comprises a first section or base 43 adapted to be welded, or otherwise secured, to the adjacent wall 3| or 32. A second section 44 extends inwardly and rearwardly from the forward edge of the base section 43, while a third section 45 projects inwardly and forwardly from the inner edge of the second section 44, the sections 44 and 45 cooperating to provide a liquid fuel collection trough or groove 46 opening upstream. A plurality of atomizing openings 41 are provided in the bottom of each trough 46 and provide for emission of air and atomized fuel from the troughs. The air for atomization of fuel from the troughs is admitted to the burner space through openings 4 48 in the walls 3| and 32, which are inclined rearwardly and are generally longitudinally aligned with the openings 41 in the bottom of the troughs 46.

The usual supply of air for combustion and cooling purposes is admitted to the burner space 33 through longitudinally-extending rows of openings 49, and additional openings 60 may be provided for directing cooling air against the gownstream surface of the ring section 44 (Fig.

While the invention has been shown in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.

What is claimed is:

1. In combustion apparatus, wall structure defining a combustion chamber having a circular side wall, a nozzle adapted to spray atomized fuel into said chamber, and a ring secured to said combustion chamber circular side wall in the path of any fuel drops deposited on said side wall by said nozzle, said ring having a fuel-receiving groove in the upstream side thereof facing said nozzle and a plurality of openings through a wall of said groove, and air admission openings in said circular side wall upstream of said groove, pairs of said side wall and groove openings lying in common axially-extending radial planes,

whereby some of the air entering said combustion chamber through said side wall openings passes through said groove openings and entrains any liquid fuel in said groove.

2. In combustion apparatus, wall structure defining an annular burner space and inner and outer overlapping annular air spaces, said structure including inner and outer annular walls separating said burner space from said inner and outer annular air spaces, respectively; an annular series of nozzles associated with said wall structure at the upstream end of said burner space and adapted to spray atomized fuel longitudinally of said burner space; and a pair of rings secured one to each of said inner and outer walls within said burner space near said annular series of nozzles, each of said rings having a liquid fuel collection groove in its upstream side, and a plurality of openings through said ring from said grooves for discharge therefrom of liquid fuel trapped therein, said inner and outer walls having air admission openings therein upstream of said ring, said wall openings and groove openings being so disposed that some of the air entering the burner space from the overlapping air spaces through said wall openings passes through said groove openings and entrains any liquid fuel collected in said grooves.

WILLARD L. CHRISTENSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,785,501 Secor Dec. 16, 1930 2,010,920 Karsel Aug. 13, 1935 2,080,425 Lysholm May 18, 1937 2,368,179 Turpin Jan. 30, 1945 2,395,418 McCollum Feb. 26, 1946 2,399,046 Larrecq Apr. 23, 1946 2,435,836 Johnson Feb. 10, 1948 

